Method of deforming cast metal



' Feb; 11, 1969 D. B. COFER METHOD OF DEFORMING CAST METAL Original Filed Aug. 2, 1965 any ,1

Warm

31 Z/VVENTOR. Dame] B. Cofer A TTORNE' Y8 United States Patent ABSTRACT OF THE DISCLOSURE A method of deforming successive lengths of a cast bar having a substantially triangular cross-section and involving deforming the cast bar with a deforming force tending to rotate the cast bar about its lengthwise axis and restricting rotation of the cast bar about this axis by resistive forces applied to a first side of the cast bar above and below this axis, to a second side above and below this axis, and to a third side.

This application is a continuation of Ser. No. 476,420, filed Aug. 2, 1965, now abandoned.

This invention relates generally to a method of aligning and guiding material and more particularly, to a method of aligning and guiding material as it is being formed in a rolling mill and in which a single guide roll is used to provide substantially all required aligning and guiding forces.

In the rolling of metals and other materials in the roll stands of conventional rolling mills, it is generally required that the material being rolled be aligned and guided as it passes between the successive roll stands of the rolling mill in order to prevent rotational motion of the material about its direction of motion. This is because such rotational motion of the material causes a twisting of the material between roll stands which results in the material being improperly formed by a subsequent roll stand.

Previously, a wide variety of rolling guides have been used to align and guide material being rolled in a rolling mill so as to prevent twisting of the material between roll stands. However, difiiculties have been encountered with these previous rolling guides.

For example, a stationary rolling guide having stationary members through which the material being rolled simply slides as it enters a roll stand has high frictional resistance to movement of the material through the rolling guide. This frictional resistance occasionally causes the material :being rolled to bind in a stationary rolling guide and customarily results in a stationary rolling guide having to be replaced frequently because of high frictional wear and tear.

Rolling guides using rolls instead of stationary members to align and guide material as it passes between the roll stands of a rolling mill generally avoid the difliculties of binding and high frictional wear normally encountered with stationary rolling guides. However, previous rolling guides of this type tend to rotate the material being rolled while serving to prevent rotation of the material by the rolls of a roll stand. This is because it is ditficult to fix and maintain the rolls of these previous rolling guides in positions with respect to each other which will not cause these rolling guides to rotate the material.

The present invention overcomes these and other difficulties encountered with previous rolling guides by using a groove in a single guide rollto apply directly to material being rolled the forces necessary to align and guide the material as it passes through the rolling guide and enters a roll stand. These forces are suflicient to prevent rotation of the material regardless of the shape of the roll pass defined by the rolls of the roll stand. A retaining roll is used simply to hold the material in the groove of the guide roll and it is not necessary to carefully fix and maintain the position of the retaining roll relative to the guide roll in order to prevent the roll guide of the invention from itself rotating the material.

The groove of the guide roll is shaped to receive a transverse cross sectional portion of the material being rolled which is sufficiently large to include the center of mass of the material being rolled, the center of mass being in the axis about which the material tends to rotate. As a result, any rotational motion of the material being rolled about its center of mass is directly resisted by forces exerted by the guide roll.

From the foregoing, it will be seen that the present invention avoids the difiiculties encountered with previous rolling guides. This is because the material being aligned and guided for entry into a roll stand is always engaged by rollers which offer no frictional resistance to the movement of the material and which have long life with a minimum of maintenance. Moreover, since only the guide roll is used to align and guide the material in a manner which prevents rotation of the material and since the retaining roll simply holds the material in the groove of the guide roll, neither the shape nor position of the retaining roll relative to the guide roll is critical as with previous rolling guides having a plurality of rolls.

The invention will be more fully understood upon consideration of the following specification and the accompanying drawings wherein like characters of reference designate corresponding parts throughout and in which:

FIG. 1 is a front elevational view of a rolling guide which may be used to practice the invention and which is installed on a rolling mill with the rolls of the rolling mill shown in dashed lines;

FIG. 2 is a cross-sectional view of the rolling guide shown in FIG. 1 taken along the line 22 of FIG. 1 and with the rolls of the rolling mill partially shown in dashed lines; I

FIG. 3 is a schematic representation of a prior art rolling guide using a plurality of rolls to position the material and which is not suited to practice the invention;

FIG. 4 is a schematic representation of the invention disclosed herein.

These figures and the following specification disclose a specific embodiment of the invention; however, it is to be understood that the invention is not limited to the specific details set forth herein since the invention may be embodied in other equivalent forms.

Referring now to FIGS. 1 and 2, a rolling guide which may be used to practice the invention comprises generally a positioning assembly and a retaining assembly designated respectively by 10a and 10b. The positioning assembly 10a comprises a thin, flat semi-circular mounting plate 11 having fixably mounted thereon a pair of guide roll mounting blocks 12 rotatably carrying a guide roll 14 therebetween. The mounting plate 11 has a semi-circular cutout 13 at approximately midway the center of the straight side thereof and the mounting blocks 12 are located to position the guide roll 14 so that material passing thereover passes through the cutout 13 without striking the'mounting plate 11. The mounting plate 11 has three elongate slots 9 therein adjacent the: curved periphery thereof for attaching the mounting plate 11 to a roll stand R of a rolling mill by bolts 13.

The guide roll 14 has a peripheral or circumferential groove 15 extending therearound and shaped to receive a cast bar 18 just prior to entering the roll stand R. The groove 15 in the embodiment of the invention shown herein, is substantially V-shaped but it will be understood that other shaped grooves may be used in the guide roll 14 depending on the shape of the material to be aligned and guided. Regardless of the shape of the groove 15, the guide roll 14 extends around the bar 18 so that the center of mass 27 of the bar 18 is within the groove 15 of the guide roll 14. Moreover, the sides of the groove 15 simultaneously contact at least four points on the periphery of the bar 18, two of these four points being above and on opposite sides of the center of mass 27 and two of these four points being below and on opposite sides of the center of mass 27 as seen in FIG. 4. It is this shape of the groove 15 that results in the bar 18 being completely aligned and guided by the guide roll 14. This can best be shown by considering a previous rolling guide using a plurality of rolls.

Referring to the schematic representations in FIGS. 3 and 4, it will be seen that although the center of mass 27 of the bar 18 lies within the groove 15 of the invention, it does not lie within the groove 15 of the previous rolling guide shown in FIG. 3. Since any force exerted by a roll stand R tending to rotate the bar 18 about its center of mass 27 will create a force couple acting about the center of mass 27 of the bar 18 and defined by horizontal components 31 and vertical components 32', this positioning of the center of mass 27 in the groove 15' of previous rolling guides requires that a plurality of rolls 14 and 21' cooperate to align and guide the bar 18. This is because the horizontal components 31' of a force couple must be resisted by reactive forces 30' exerted by the roll 14 and by reactive forces 33' exerted by the roll 21'. Similarly, the vertical components 32 of a force couple tending to rotate the bar 18 must be resisted by reactive forces 34' exerted by the roll 14' and by reactive forces 35' exerted by the roll 21.

On the other hand, it will be seen from FIG. 4 that by engaging the bar 18 at a plurality of points distributed above, below, and on opposite sides of the center of mass 27, the guide roll 14 by itself exerts both the reactive forces 30 and the reactive forces 33 necessary to prevent rotation of the bar 18 by the horizontal components 31 of a force couple. Similarly, the guide roll 14 by itself exerts both the reactive forces 34 and the reactive forces 35 necessary to prevent rotation of the bar 18 by the vertical components 32 of a force couple.

It will be understood that this is because the reactive forces 34 and 35 serve with the reactive forces 30 and 33 to fix the positions of the sides S of the cast bar 18 both above and below the center of mass 27 and that it is this fixing of the positions of the sides S of the cast bar 18 which results in the guide roll 14 serving to prevent rotation of the cast bar 18 about its center of mass 27 by either horizontal components 31 or vertical components 32 of force couples. In contrast, and as shown in FIG. 3, previous rolling guides are able to resist twisting of the material by force couples only by reactive forces exerted by both rolls 14' and 21.

The retaining assembly b comprises a thin semicircular mounting plate 19 having the same shape as the mounting plate 11. A pair of retaining roll mounting blocks 20 are carried by the plate 19 and rotatably carried between the blocks 20 is a retaining roll 21. The mounting plate 19 has a semi-circular cutout 23 at approximately the midpoint of the straight side thereof, corresponding to the cutout 13 in the mounting plate 11. The retaining roll 21 is positioned with respect to the cutout 23 so that when the retaining roll 21 is in contact with a cast bar 18 received in the groove of the guide roll 14, the cast bar 18 passes through the cutout 23 without striking the mounting plate 19. The retaining roll 21 may have a flat, outer periphery as shown in FIG. 4 or it may have a shallow groove extending around the periphery thereof as shown at 24 in FIG. 1. This is because the retaining roll 21 merely serves to retain the cast bar 18 within the groove 15 of the guide roll 14. In the rolling guide described for practicing the invention disclosed herein, the just slightly concave shape of the groove 24 serves to conform with one side of the cast bar 18, but it will be understood that no groove 24 is required in the retaining roll 21 since it does not serve to align or guide the bar 18.

The mounting plate 19 has a plurality of elongate slots 2'5 therein to receive bolts 26 therethrough for attaching the mounting plate 19 to the roll stand R of a rolling mill. These elongate slots 25 and the elongate slots 9 in the mounting plate 11 permit the positions of the guide roll 14 and the retaining roll 21 to be adjusted to the size of the cast bar 18 and for the desired path of the cast bar 18 into the rolls of the roll stand R.

With the rolling guide shown in FIGS. 1 and 2, the

method of deforming cast metal shown schematically in.

FIG. 4 is adapted for use on a rolling mill where a roll stand (not shown) rolls the bar 18 into the generally triangular shape shown in FIG. 1 and the roll stand R rolls the bar into a generally circular or similar shape by a rolling action which tends to twist the cast bar 18 about its axis of rotation as it moves toward and into the roll stand R. However, it will be understood that the present inventive concept is not limited to these particular shapes of cast bar 18, but may be easily modified to provide for deforming cast bars 18 having other transverse cross-sectional shapes.

Moreover, it will also be understood that the embodiments shown herein are shown by way of illustration only,

and are meant in no way to be restrictive; therefore, numerous changes and modifications may be made, and the full use of equivalents resorted to without departing from the spirit or scope of the invention as outlined by the appended claims.

I claim:

1. In a method of deforming successive lengths of a cast bar having a substantially triangular cross section transverse to a lengthwise axis, deforming a first length of said cast bar with a deforming force tending to rotate said cast bar about said axis, and restricting rotation of said cast bar about said axis by a plurality of resistive forces, at least some of said resistive force being applied to a first side of a second length of said cast bar above and below said axis and at least others of said resistive forces being applied to a second side of said second length of said cast bar above and below said axis.

2. The method of claim 1 in which at least one of said resistive forces is applied to a third side of said second length of said cast bar.

3. The method of claim 2 in which said one of said resistive forces maintains said second length of said cast bar in position for the application of said some of said resistive forces and said others of said resistive forces.

4. The method of claim 1 in which said plurality of resistive forces are applied to said second length of said cast bar in a direction substantially transverse to said axis.

References Cited UNITED STATES PATENTS 2,014,855 9/1935 Lowndes 193-35 3,063,533 11/1962 Cook 193-35 FOREIGN PATENTS 822,831 11/ 1959 Great Britain.

CHARLES W. LANHAM, Primary Examiner.

E. SUTTON, Assistant Examiner. 

